U.S. patent number 10,623,619 [Application Number 16/373,796] was granted by the patent office on 2020-04-14 for image-capture-scope indication device for image-capture apparatus.
This patent grant is currently assigned to INTERNATIONAL BUSINESS MACHINES CORPORATION. The grantee listed for this patent is INTERNATIONAL BUSINESS MACHINES CORPORATION. Invention is credited to Hao Chang, Yan Zheng Sun, Lijun Wei, Qing Hong Zhuang.
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United States Patent |
10,623,619 |
Chang , et al. |
April 14, 2020 |
Image-capture-scope indication device for image-capture
apparatus
Abstract
An image-capture-scope indication device for an image-capture
apparatus. The image-capture-scope indication device includes: a
light source, fixed on a surface of the image-capture apparatus on
which a lens of the image-capture apparatus is provided; a light
ray selection member, which is provided in front of the light
source and has a light transmission portion; and a drive member.
The drive member is configured for moving the light ray selection
member so that a scope surrounded by light rays emitted from the
light source and passing through the light transmission portion of
the light ray selection member is provided that is consistent with
an image-capture-scope of the image-capture apparatus.
Inventors: |
Chang; Hao (Beijing,
CN), Sun; Yan Zheng (Beijing, CN), Wei;
Lijun (Beijing, CN), Zhuang; Qing Hong (Beijing,
CN) |
Applicant: |
Name |
City |
State |
Country |
Type |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
Armonk |
NY |
US |
|
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Assignee: |
INTERNATIONAL BUSINESS MACHINES
CORPORATION (Armonk, NY)
|
Family
ID: |
55828577 |
Appl.
No.: |
16/373,796 |
Filed: |
April 3, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190230263 A1 |
Jul 25, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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14887500 |
Oct 20, 2015 |
10375281 |
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Foreign Application Priority Data
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Oct 31, 2014 [CN] |
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2014 1 0601690 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04N
5/2254 (20130101); H04N 5/2259 (20130101); G02B
7/08 (20130101); H04N 5/225 (20130101) |
Current International
Class: |
G02B
7/08 (20060101); H04N 5/225 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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103048853 |
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Apr 2013 |
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CN |
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103516965 |
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Jan 2014 |
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CN |
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WO2008/059323 |
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May 2008 |
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WO |
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Other References
IBM Corporation, "A Position Accurate Self-Shooting Method for
Camera", IP.com Disclosure No. IPCOM00016680, Jan. 24, 2008 (3
pages). cited by applicant .
Chang et al., "List of IBM Patents and/or Patent Applications
Treated as Related", U.S. Appl. No. 16/373,796, filed Apr. 3, 2019,
dated Apr. 3, 2019 (2 pages). cited by applicant.
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Primary Examiner: Dzierzynski; Evan P
Attorney, Agent or Firm: McNamara, Esq.; Margaret A.
Radigan, Esq.; Kevin P. Heslin Rothenberg Farley & Mesiti
P.C.
Claims
The invention claimed is:
1. An image-capture-scope indication device for an image-capture
apparatus, comprising: a light source, the light source being fixed
on a surface of the image-capture apparatus on which a lens of the
image-capture apparatus is provided; a light ray selection member,
the light ray selection member being provided in front of the light
source and having a light transmission portion; a drive member, the
drive member being configured for moving the light ray selection
member so that a scope surrounded by light rays emitted from the
light source and passing through the light transmission portion of
the light ray selection member is consistent with an
image-capture-scope of the image-capture apparatus; and wherein the
light source comprises a first light source, a second light source,
a third light source and a fourth light source, which are
respectively provided on four different sides of the lens of the
image-capture apparatus, and which are collectively arranged in a
shape of a rectangle about the lens of the image-capture
apparatus.
2. The image-capture-scope indication device of claim 1, wherein:
the light ray selection member comprises a first light ray
selection member and a second light ray selection member; a first
light transmission portion and a second light transmission portion
are provided on the first light ray selection member; a third light
transmission portion and a fourth light transmission portion are
provided on the second light ray selection member; and the first
light transmission portion, the second light transmission portion,
the third light transmission portion and the fourth light
transmission portion are associated with the first light source,
the second light source, the third light source and the fourth
light source, respectively.
3. The image-capture-scope indication device of claim 2, wherein
extension directions of the first light transmission portion, the
second light transmission portion, the third light transmission
portion and the fourth light transmission portion are respectively
same as those of the first light source, the second light source,
the third light source and the fourth light source.
4. The image-capture-scope indication device of to claim 2,
wherein: the drive member comprises a first connector, a second
connector and a gear; the first connector is fixed to the first
light ray selection member, and the second connector is fixed to
the second light ray selection member; and the gear is provided
between the first connector and the second connector, so that the
gear drives the first connector and the second connector to move
when the gear rotates, and then, the first connector and the second
connector respectively drive the first light ray selection member
and the second light ray selection member to move.
5. The image-capture-scope indication device of claim 4, wherein:
patterns capable of engaging with the gear are provided on a
surface of the first connector facing the gear, so as to engage the
first connector with the gear; and patterns capable of engaging
with the gear are provided on a surface of the second connector
facing the gear, so as to engage the second connector with the
gear.
6. The image-capture-scope indication device of claim 4, wherein
the gear is coaxial with the lens and is bonded with the lens.
7. The image-capture-scope indication device of claim 6, wherein
the lens drives the drive member to move when the lens moves
backward or forward to perform a focusing action.
8. The image-capture-scope indication device of claim 4, wherein
when the gear rotates clockwise, the first connector and the second
connector drive the first light ray selection member and the second
light ray selection member so that the first light ray selection
member and the second light ray selection member gradually close to
each other; and upon closing, a scope surrounded by the light rays
passing through the first light transmission portion, the second
light transmission portion, the third light transmission portion
and the fourth light transmission portion is reduced.
9. The image-capture-scope indication device of claim 4, wherein
when the gear rotates counterclockwise, the first connector and the
second connector drive the first light ray selection member and the
second light ray selection member so that the first light ray
selection member and the second light ray selection member
gradually become away from each other; and at this time, the scope
surrounded by the light rays passing through the first light
transmission portion, the second light transmission portion, the
third light transmission portion and the fourth light transmission
portion is enlarged.
10. The image-capture-scope indication device of claim 1, wherein
each of the first light source, the second light source, the third
light source and the fourth light source is a scattering light
source.
11. The image-capture-scope indication device of claim 1, wherein a
light emitted from each of the first light source, the second light
source, the third light source and the fourth light source is
visible light.
12. The image-capture-scope indication device of claim 1, wherein a
region surrounded by the first light source, the second light
source, the third light source and the fourth light source has a
same shape and a proportional size as a negative captured by the
image-capture apparatus.
13. The image-capture-scope indication device of claim 1, wherein
the light rays emitted from the light source and passing through
the light transmission portion of the light ray selection member
has an outgoing angle B, and the outgoing angle B meets a
relationship as below: B=arc tan((u*tan A-d)/u); and A=2.times.arc
tan(D/2f) where u is an object distance; d is a distance between
the light source and the lens of the image-capture apparatus; A is
a visual angle; D is a length of a diagonal line of the negative of
the image-capture apparatus, and f is a focus.
14. The image-capture-scope indication device of claim 13, wherein:
the image-capture-scope indication device further comprises a
control member, and the control member is in signal connection with
the drive member; and when the image-capture apparatus takes an
image, the control member determines the outgoing angle B by
calculation, and then controls the drive member to drive the light
ray selection member to move according to the determined outgoing
angle B.
15. The image-capture-scope indication device of claim 1, wherein
the light rays emitted from the light source and passing through
the light transmission portion of the light ray selection member
has an outgoing angle B, and the outgoing angle B meets a
relationship as below: R.apprxeq.2*arc tan(D/2f) where D is a
length of a diagonal line of the negative of the image-capture
apparatus, and f is a focus.
16. The image-capture-scope indication device of claim 15, wherein:
the image-capture-scope indication device further comprises a
control member, and the control member is in signal connection with
the drive member; and when the image-capture apparatus takes an
image, the control member determines the outgoing angle B by
calculation, and then controls the drive member to drive the light
ray selection member to move according to the determined outgoing
angle B.
17. The image-capture-scope indication device of claim 1, wherein
the image-capture-scope indication device is installed inside a
shell of the image-capture apparatus, and a portion of the shell
corresponding to the image-capture-scope indication device is made
of a transparent material.
Description
BACKGROUND
An image-capture apparatus is capable of taking still images and/or
videos, and thus can play an important role in people's daily life.
From traditional film type to the present digital type, and from
traditional manual focusing to the present eye-control tracking,
continually improving techniques relating with the image-capture
apparatus have brought us more and more conveniences. However, even
so, traditional image-capture apparatuses may have shortcomings and
be inconvenient to use in certain aspects. For example,
image-capture-scope of an image-capture apparatus cannot be known
in cases such as noted below, resulting in inconvenience for the
photographer, as well as a person inside or outside the
image-capture-scope.
For instance, when a photographer takes a self-image, a remote
controller or a timer may be used to take the picture. Generally,
the photographer may estimate a position through a lens of the
image-capture apparatus, and then leave the image-capture apparatus
to the vicinity of the estimated position; however, once the
photographer leaves the image-capture apparatus, the current
image-capture-scope is uncertain, and thus errors may occur.
As another example, a person inside or outside an
image-capture-scope cannot know the current image-capture-scope,
and so they cannot determine their own relative positions to the
image-capture-scope.
In above-noted cases, the photographer, or the person inside or
outside the image-capture-scope, would benefit from a convenient
and fast way to determine a current image-capture-scope.
SUMMARY
In one or more aspects, an image-capture-scope indication device is
provided for an image-capture apparatus. The image-capture-scope
indication device includes, for instance: a light source, the light
source being fixed on a surface of the image-capture apparatus on
which a lens of the image-capture apparatus is provided; a light
ray selection member, the light ray selection member being provided
in front of the light source and having a light transmission
portion; and a drive member, the drive member being configured for
moving the light ray selection member so that a scope surrounded by
light rays emitted from the light source and passing through the
light transmission portion of the light ray selection member is
consistent with an image-capture-scope of the image-capture
apparatus. The light source includes a first light source, a second
light source, a third light source, and a fourth light source,
which are respectively provided on four different sides of the lens
of the image-capture apparatus, and which are collectively arranged
in a shape of a rectangle about the lens of the image-capture
apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
Through the more detailed description below of certain embodiments
of the present invention depicted in the accompanying drawings, the
above and other objects, features and advantages of the present
disclosure will become more apparent, wherein the same reference
numbers throughout multiple figures generally refer to the same or
similar components, and wherein:
FIG. 1 is a schematic view illustrating an image-capture-scope
indication device for an image-capture apparatus, according to one
or more aspects of the present invention;
FIG. 2 is a schematic view illustrating a light source of an
image-capture-scope indication device for the image-capture
apparatus, according to one or more aspects of the present
invention;
FIG. 3 is a light path schematic illustrating an image-capture
principle of a camera, useful in understanding an
image-capture-scope indication device, according to one or more
aspects of the present invention; and
FIG. 4 is a light path schematic for determining an outgoing angle
B of light rays emitted from the light source and passing through a
light transmission portion of a light ray selection member, useful
in understanding an image-capture-scope indication device,
according to one or more aspects of the present invention.
DETAILED DESCRIPTION
One or more embodiments of an image-capture-scope indication
device, in accordance with one or more aspects of the present
invention, are described in detail below with reference to the
accompanying drawings, in which one or more embodiments of the
present disclosure have been illustrated. However, the present
disclosure can be implemented in various manners, and thus should
not be construed to be limited to the embodiment(s) disclosed
herein.
Unless otherwise defined, the technical and scientific terms used
herein have the same meanings as commonly understood by one of
ordinary skill in the art to which the disclosure belongs. The
terms "first," "second," etc., which are used in the description
and the claims of the disclosure, are not intended to indicate any
sequence, amount or importance, but distinguish various components.
Also, the terms such as "a," "an," etc., are not intended to limit
the amount, but indicate the existence of at least one. The terms
"comprise," "comprising," "include," "including," etc., are
intended to specify that the elements or the objects stated before
these terms encompass the elements or the objects and equivalents
thereof listed after these terms, but do not preclude the other
elements or objects. "On," "under," "right," "left" and the like
are only used to indicate relative position relationship, and when
the position of the object which is described is changed, the
relative position relationship may be changed accordingly.
According to one or more embodiments of the disclosure, an
image-capture-scope indication device of an image-capture apparatus
is provided. The image-capture-scope indication device comprises: a
light source, fixed on a surface of the image-capture apparatus on
which a lens of the image-capture apparatus is provided; a light
ray selection member, provided in front of the light source and
having a light transmission portion; and a drive member, configured
for moving the light ray selection member so that a scope
surrounded by light rays emitted from the light source and passing
through the light transmission portion of the light ray selection
member is consistent with an image-capture-scope of the
image-capture apparatus.
In one or more embodiments of the image-capture-scope indication
device disclosed herein, the scope surrounded by the light rays
emitted from the light source and passing through the light
transmission portion of the light ray selection member is
consistent with the image-capture-scope of the image-capture
apparatus, and thus a photographer, a person inside the
image-capture-scope and a person outside the image-capture-scope
can directly judge and determine the current image-capture-scope of
the image-capture apparatus by observing the scope surrounded by
the light rays emitted from the light transmission portion.
Therefore, by adopting an image-capture-scope indication device
such as disclosed herein, a photographer can easily judge the
location of the image-capture-scope and, thereby allowing for
improvement in the quality of the resultant image. Moreover, by
adopting an image-capture-scope indication device as disclosed, any
person inside the image-capture-scope or a person outside the
image-capture-scope can conveniently judge the current
image-capture-scope at any time; and can thereby easily determine
their own relative position relative to the
image-capture-scope.
It should be noted that an image-capture apparatus, such discussed
in the embodiments of the disclosure described herein, may be an
apparatus for taking still images and/or videos, such as a camera,
a video camera or any other products or components with
image-capture function.
It should also be noted that the image-capture-scope of the
image-capture apparatus mentioned in the embodiments of the
disclosure described herein means, for instance, a maximum scope
seen through the lens of the image-capture apparatus in the case
that an object distance u, an image distance v and a focus f meet
the relationship: 1/v=1/f-1/u.
FIG. 1 is a schematic view illustrating one embodiment of an
image-capture-scope indication device for an image-capture
apparatus, according to one or more aspects of the present
invention; and FIG. 2 is a schematic view illustrating a light
source of an image-capture-scope indication device for the
image-capture apparatus, according to one or more aspects of the
present invention. With reference to FIG. 1 and FIG. 2, an
image-capture-scope indication device according to one or more
embodiments of the disclosure is described below.
In FIG. 1, the light source is not shown for the reason of angle of
view. Referring to FIG. 2, the light source includes, in one
embodiment, a first light source 11, a second light source 12, a
third light source 13 and a fourth light source 14, which are
respectively provided on four sides of a lens of the image-capture
apparatus. For example, first light source 11 and third light
source 13 extend along a horizontal direction; and second light
source 12 and fourth light source 14 extend along a vertical
direction. In one or more implementations, a region surrounded by
first light source 11, second light source 12, third light source
13 and fourth light source 14 has a same shape and a proportional
size as a negative of the image-capture apparatus. For example, the
region surrounded by first light source 11, second light source 12,
third light source 13 and fourth light source 14 is in a shape of a
rectangle or square. Note that in the depicted example, first light
source 11, second light source 12, third light source 13 and fourth
light source 14 are not connected to each other (as shown in FIG.
2). Alternatively, first light source 11, second light source 12,
third light source 13 and fourth light source 14 could be connected
to each other (not shown); or two or three of the first light
source 11, second light source 12, third light source 13 and fourth
light source 14 may be connected in series (not shown).
Each of the first light source 11, second light source 12, third
light source 13 and fourth light source 14 may be a scattering
light source; that is, each source may have outgoing light rays at
any angles within a preset angle range. By way of example, the
preset angle range may be from 0 degree to 20 degree; and in that
case, each of the first light source 11, second light source 12,
third light source 13 and fourth light source 14 may have outgoing
light rays at any angles from 0 degree to 20 degree. The light
emitted from each of first light source 11, second light source 12,
third light source 13 and fourth light source 14 may be visible
light. For example, the light emitted from each of first light
source 11, second light source 12, third light source 13 and fourth
light source 14 may be visible monochromatic light, such as red,
blue or green light.
With reference to FIG. 2, a distance "d" may be provided between
first light source 11 and the lens of the image-capture apparatus;
for example, d is from 1 cm to 8 cm. Furthermore, there exists a
distance between second light source 12, third light source 13,
fourth light source 14 and the lens of the image-capture apparatus,
respectively. In order to simplify the manufacture process, the
distances between first light source 11, second light source 12,
third light source 13, fourth light source 14 and the lens of the
image-capture apparatus may be equal to each other, as shown in
FIG. 2. However, in practice, the distances between first light
source 11, second light source 12, third light source 13, fourth
light source 14 and the lens of the image-capture apparatus may be
different from each other. Note, in this regard, that operation of
the image-capture-scope indication device will not be obviously
influenced even through the distances between first light source
11, second light source 12, third light source 13, fourth light
source 14 and the lens of the image-capture apparatus are different
from each other, which will be described below in detail.
In one or more implementations, each of first light source 11,
second light source 12, third light source 13 and fourth light
source 14 may be a line light source, such as a light tube as shown
in FIG. 2.
Alternatively, each of the first light source 11, second light
source 12, third light source 13 and fourth light source 14 is a
spot light source or a combination of a plurality of spot light
sources.
It should be noted that, sizes of first light source 11, second
light source 12, third light source 13 and fourth light source 14
may be substantially the same to each other, as shown in FIG. 2.
However, in practice, the sizes of first light source 11, second
light source 12, third light source 13 and fourth light source 14
may be alternatively different from each other.
Referring to FIG. 1, the light ray selection member may include a
first light ray selection member 20 and a second light ray
selection member 30; with a first light transmission portion 21 and
a second light transmission portion 22 being provided on first
light ray selection member 20; and a third light transmission
portion 31 and a fourth light transmission portion 32 being
provided on the second light ray selection member 30.
The first light transmission portion 21, second light transmission
portion 22, third light transmission portion 31 and fourth light
transmission portion 32 are associated with or correspond to first
light source 11, second light source 12, third light source 13 and
fourth light source 14, respectively. More specifically, extension
directions of the first light transmission portion 21, second light
transmission portion 22, third light transmission portion 31 and
fourth light transmission portion 32 are respectively same as those
of first light source 11, second light source 12, third light
source 13 and fourth light source 14. As noted above, the drive
member is configured for moving the light ray selection member; and
in this case, the movement ranges of first light transmission
portion 21, second light transmission portion 22, third light
transmission portion 31 and fourth light transmission portion 32
are required to at least partially overlap with the light ray
ranges of first light source 11, second light source 12, third
light source 13 and fourth light source 14, respectively.
By way of example, the first light ray selection member 20 is in a
shape of L; and first light transmission portion 21 and second
light transmission portion 22 are respectively provided on the two
sides of the L shape, as shown in FIG. 1. Further, second light ray
selection member 30 is also shown in a shape of L; and third light
transmission portion 31 and fourth light transmission portion 32
are respectively provided on the two sides of the L shape.
In one or more implementations, first light transmission portion
21, second light transmission portion 22, third light transmission
portion 31 and fourth light transmission portion 32 are formed of
small holes in a row, respectively. The distances between the small
holes may be even or uneven. Furthermore, first light transmission
portion 21, second light transmission portion 22, third light
transmission portion 31 and fourth light transmission portion 32
may be in other forms, such as slit, transmission film or the
like.
Referring to FIG. 1, the drive member may comprise a first
connector 40, a second connector 50 and a gear 60. First connector
40 may be fixed to first light ray selection member 20, second
connector 50 may be fixed to second light ray selection member 30
and gear 60 is provided between first connector 40 and second
connector 50, so that gear 60 drives first connector 40 and second
connector 50 to move when the gear 60 rotates. First connector 40
and second connector 50 respectively drive first light ray
selection member 20 and second light ray selection member 30 to
move.
As an example, first connector 40 and second connector 50 may be
formed as straight plates. For example, patterns capable of
engaging with gear 60 can be provided on a surface of first
connector 40 facing gear 60, so as to engage first connector 40
with gear 60, and patterns capable of engaging with gear 60 may be
provided on a surface of second connector 50 facing gear 60, so as
to engage second connector 50 with gear 60.
In the depicted example, an extension direction of first connector
40 is in parallel with that of second connector 50.
As described above, first light ray selection member 20 and second
light ray selection member 30 may be in the shape of L, and in such
case, first connector 40 may be provided between two sides of the
L-shaped first light ray selection member 20 and second connector
50 may be provided between two sides of the L-shaped second light
ray selection member 30. For example, an angle between the first
connector 40 and each side of the L-shaped first light ray
selection member 20 may be 45 degrees, and an angle between second
connector 50 and each side of L-shaped second light ray selection
member 30 is 45 degrees.
In one or more embodiments, gear 60 is coaxial with the lens of the
image-capture apparatus and is bonded with the lens of the
image-capture apparatus. The gear 60 being coaxial with the lens
means that a central axis of the gear 60 coincides with an optical
axis of the lens. Gear 60 may be directly or indirectly bonded with
the lens. For example, inside threads may be provided on the inner
wall of the gear 60, and corresponding outside threads may be
provided on the lens with the inside threads engaging with the
outside threads so that gear 60 is directly bonded with the lens.
For example, inside threads may be provided on the inner wall of
gear 60, and inside threads may also be provided on the lens; both
of inside threads of gear 60 and inside threads of the lens engage
with corresponding outside threads formed on a shaft, so that gear
60 is indirectly bonded with the lens. It should be noted that, the
method for bonding gear 60 with the lens is not limited to adopting
inside threads and outside threads described as above, and any
known bonding method may be adopted.
In the case that the gear is coaxial with the lens of the
image-capture apparatus and is bonded with the lens of the
image-capture apparatus, the lens is capable of driving the gear to
rotate clockwise or counter-clockwise when the lens moves backward
or forward to perform a focusing action. In this way, the lens is
capable of driving the drive member to move when the lens moves
backward and forward to perform the focusing action, and then the
drive member drives the light ray selection member to move.
Therefore, the image-capture-scope indication device according to
the embodiments of the disclosure can operate without adding an
exclusive power source.
Referring to FIG. 1, when gear 60 rotates clockwise, first
connector 40 and second connector 50 drive first light ray
selection member 20 and second light ray selection member 30 so
that the first light ray selection member 20 and the second light
ray selection member 30 gradually close to each other; and at this
time, a scope surrounded by the light rays passing through first
light transmission portion 21, second light transmission portion
22, third light transmission portion 31 and fourth light
transmission portion 32 is reduced. When gear 60 rotates
counter-clockwise, first connector 40 and second connector 50 drive
first light ray selection member 20 and second light ray selection
member 30 so that first light ray selection member 20 and second
light ray selection member 30 gradually move away from each other,
and at this time, the scope surrounded by the light rays passing
through first light transmission portion 21, second light
transmission portion 22, third light transmission portion 31 and
fourth light transmission portion 32 is enlarged.
As described above, in an image-capture-scope indication device
according to the embodiments of the present disclosure, the drive
member drives the light ray selection member to move, so that the
relative position between the light ray selection member and the
light source changes and the outgoing angle of the light rays
passing through the light transmission portion of the light ray
selection member changes as well. In this way, the light rays
passing through the light transmission portion of the light ray
selection member are selected by the drive member driving the light
ray selection member to move. In order that the scope surrounded by
the light rays passing through the light transmission portion of
the light ray selection member is consistent with the
image-capture-scope of the image-capture apparatus, the light rays
passing through the light transmission portion of the light ray
selection member will have a specific outgoing angle B.
Hereinafter, the outgoing angle B will be determined in conjunction
with FIG. 3 and FIG. 4.
FIG. 3 is a light path schematic view illustrating an image-capture
principle of a camera. In order to obtain a clear image, the object
distance u, the image distance v and the focus f meet the
relationship: 1/v=1/f-1/u (1)
Besides, for the image-capture apparatus, the maximum scope
(namely, image-capture-scope) seen through the lens may be
expressed by a visual angle A; and the relationship between the
visual angle A and the focus f is: A=2.times.arc tan(D/2f) (2)
Where arc tan is the arc tangent function, and D is a length of a
diagonal line of the negative of the image-capture apparatus. It
can be seen that the larger the focus is, the smaller the visual
angle is; on the contrary, the smaller the focus is, the larger the
visual angle is.
FIG. 4 is a light path schematic view for determining the outgoing
angle B of light rays emitted from the light source and passing
through the light transmission portion of the light ray selection
member. Referring to FIG. 4, in order that the scope surrounded by
the light rays passing through the light transmission portion of
the light ray selection member is consistent with the
image-capture-scope of the image-capture apparatus, the outgoing
angle B of the light rays passing through the light transmission
portion will meet the following relationship: Tan B=(X-m)/u (3)
X=u*tan A+r (4) Where X is a radius of the image-capture-scope; m
is a distance between the light source and a center of the lens; r
is a radius of the lens. In combination with the previous
descriptions, it can be known that m is a sum of the radius r of
the lens and the distance d between the light source and the lens,
namely, m=r+d.
The relationship formula (4) is substituted into the relationship
formula (3) to obtain: Tan B=(X-m)/u=(u*tan A+r-m)/u (5)
Further, in conjunction with the relationship formula m=r+d, it can
be obtained through the relationship formula (5) that: B=arc
tan((*tan A+r-m)/u)=arc tan((*tan A-d)/u) (6)
If it continues, we can see that tan A can be replaced by variables
D and f; finally, it can be obtained that the outgoing angle B is a
function of D, f, u (as described above, d is a fixed value); the
dependence relationship of the outgoing angle B on D, f, u can be
mathematically modeled. It can be seen that the outgoing angle B is
only determined by D and f when the object distance u is given.
Further, the distance d between the light source and the lens is
far less than the object distance u, so the outgoing angle B is
approximately equal to the visual angle A according to the formula
(6): B.apprxeq.A=2*arc tan(D/2f) (7)
In practice, the distance d between the light source and the lens
generally is far less than the object distance u, so the outgoing
angle B can be approximately calculated according to formula
(7).
When the image-capture-scope indication device according to the
embodiments of the disclosure is adopted, the outgoing angle B is
firstly calculated according to formula (6) or (7); and then the
drive member is controlled to drive the light ray selection member
to move, so that the light rays with the outgoing angle B are
selected to pass through the light transmission portion of the
light ray selection member. In this way, the scope surrounded by
the light rays passing through the light transmission portion is
consistent with the image-capture-scope of the image-capture
apparatus. For example, the image-capture-scope indication device
according to the embodiments of the disclosure further comprises a
control member, and the control member is in signal connection with
the drive member. When the image-capture apparatus takes the image,
the control member determines the outgoing angle B according to
formula (6) or (7), and then controls the drive member to drive the
light ray selection member to move according to the determined
outgoing angle B.
In an image-capture-scope indication device according to one or
more embodiments of the present disclosure, the scope surrounded by
the light rays emitted from the light source and passing through
the light transmission portion of the light ray selection member is
consistent with the image-capture-scope of the image-capture
apparatus, and thus a photographer, person inside the
image-capture-scope and/or person outside the image-capture-scope
can directly judge and determine the current image-capture-scope of
the image-capture apparatus by observing the scope surrounded by
the light rays emitted from the light transmission portion.
Therefore, by adopting the image-capture-scope indication device
according to one or more aspects of the present invention, the
photographer can easily judge the location of the
image-capture-scope and thereby improve the quality of the
resultant image. Moreover, by adopting an image-capture-scope
indication device as disclosed herein, any person inside the
image-capture-scope and/or a person outside the image-capture-scope
can conveniently judge the current image-capture-scope at any time;
and can thereby easily determine their own position relative to the
image-capture-scope.
Besides, it can be seen from the formulas (6) and (7) that the
influence of the distance d between the light source and the lens
on the outgoing angle B can be nearly ignored for the distance d
between the light source and the lens is far less than the object
distance u, and it is just the reason why the distances between the
first light source 11, the second light source 12, the third light
source 13, the fourth light source 14 and the lens may be equal to
or different from each other.
It should be noted that, the image-capture-scope indication device
according to the embodiments of the disclosure may be provided with
a switch; thus the image-capture-scope indication device can be
conveniently controlled to be in a working state or not in a
working state.
It should be noted that, the image-capture-scope indication device
according to the embodiments of the disclosure may be remotely
controlled; thereby the image-capture-scope indication device can
be conveniently controlled from a remote place.
It should be noted that, the image-capture-scope indication device
according to the embodiments of the disclosure may be mounted
outside or inside the shell of the image-capture apparatus. When
the image-capture-scope indication device is installed inside the
shell, a portion of the shell corresponding to the
image-capture-scope indication device is made of a transparent
material.
The descriptions of the various embodiments of the present
disclosure have been presented for purposes of illustration, but
are not intended to be exhaustive or limited to the embodiments
disclosed. Many modifications and variations will be apparent to
those of ordinary skill in the art without departing from the scope
and spirit of the described embodiments. The terminology used
herein was chosen to best explain the principles of the
embodiments, the practical application or technical improvement
over technologies found in the marketplace, or to enable others of
ordinary skill in the art to understand the embodiments disclosed
herein.
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